Improvement in air-compressors



E. HILL, In

AIR-COMPRESSER,

Patented Jan. 4v. 1876.

f gm@ MM W71 N. PETERS. PHOTO-LIT MOGRAPMER. WASHINGTON. D. C.

UNITED STATES PATENT OFFICE.

EBENEZER HILL, JR., OF SOUTH NORWALK, CONNECTICUT.

IMPROVEMENT IN AIR-COMPRESSORS.

Specication forming part of Letters Patent N o. 17 1,805, dated January 4, 1876 5. application led June 6, 1874.

To all whom @t may concern:

Be it known that I, EBENEZER HILL, Jr., of South Norwalk, Fairljeld county', and State of Connecticut, have invented a new and useful Lnprovementin Air-Compressors and Vacuum-Pumps; and l hereby declare that the following is a full, clear, and exact description thereof, reference being had to the accompanying drawings, making a part of Athis specification, and the letters of reference marked thereon, in which the same letter represents the same thing in each tigure.

Figure l is a cut section of my improve'l compressor; Fig. 2, a plan view otl the same.

The letters correspond to like parts in each View.

My invention relates to certain improvements in apparatus for compressing air, the object being to equalize the resistance ot' the air during the entire length ot' piston stroke, as will be hereinafter fully described, and it consists oftwo cylinders ofditterent diameters, having pistons Working upon the samepistonrod, and moving together in the same plane, the two cylinders being connected together by suitable valves or pipes, as will be hereinafter fully described. The air is driven at each stroke of the pistons from the large cylinder into the smaller one, where it is partially compressed, the return stroke further compressing the partially-compressed air, and forcing it out to point of consumption, as will be fully hereinafter set forth. y

A description of the operation ofthe valves and mechanism upon one side ot' the piston will suffice to explain the Whole, as the machine is double-acting, and the operation of the mechanism upon the other side of the piston is precisely the same.

H is alarge cylinder; P, a smaller one, joined to H in the manner shown and herein described, The pistons L and K, lbeing upon the same rod M, move together. While the pistons move from left to right the air is drawn into f the space B of the cylinder H through the valve C. Upon the return stroke, from right to left, the air is forced by the piston L through the valve D, along the passage in the direction ofthe arrows, into the space E of the cylinder P. The cylinder P being smaller than H,a partial compression takes place when the air is forced in E. Upon the next forward stroke ot' the pistons, from left to right, the piston K compresses the air i-n E, and forces it through the valve F into the pipe G, the valve D closing meanwhile, from whence it is conducted oli' for use. During this same stroke the piston L inspires the air again through the valve C, and theoperation is repeated, as above described.

Valves I, J, and .N perform, respectively, the same oftces as valves' C, D, and F upon the other side ofthe pistons.

When deemed expedient a third cylinder can also be used with advantage.

The combination of two communicating double-acting engines with cylinders of unequal diameterstheir pistons mounted on the same rodand moving together, as described,

to gradually compress the air, and equalize the reslstance atl the commencement and tervmination of the piston strokes, substantially as set forth.

' EBENEZElSt HILL, JR. Witnesses:

GEo. H. COLLINS, JOHN W. RIPLEY. 

